How do I timeout waiting for `input`?

Question

Lets say:

import.time

print('Make a guess: ')

time.sleep(0.5)

guess = input()

if guess == 45:
   print('Correct')

I only want this to work if 45 is written in less than 4 seconds. How do I do that?

Answer 1

The simplest thing you can do is to keep track of the time spent:

import time

start = time.time()
guess = input()
end = time.time()

if end-start > 4:
    print('Sorry, you took too long!')
elif guess == '45':
    print("Hooray! You're right!")
else:
    print('Nope, sorry.')

note: I also changed 45 to '45', because input returns a string in Python3. If you're using Python2, you should use guess = raw_input() instead.